Marking pen



FIG. 1 is a perspective view of a marking pen showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a bottom elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a plan elevational view thereof;

FIG. 6 is a left side view thereof; and,

FIG. 7 is a right side view thereof. 

The ornamental design for a marking pen, as shown and described. 